Duplex carburetor



lll/1119475.

. fllllralfll' l l &

2 Sheets-Sheet l C. G. KREBS DUPLEX CARBURETOR Filed May 21, 1924 vl/Enron Canin. G .Knees Mp5 mmfssfs #IMM C. G. KREBS .DUPLEX cARBURETon Filed May 2l. 1924 2 Sheets-Sheet 2 W/ Hf /A W/TNESSES IN VEN TOH I v CHREL G. KRsas *,4 nonwfrs Patented Oct. 6, 1925.

UNITED STATESv :PATENT oFFlori.g

CAREL GOVERT KREBS, Oli' BROOKLYN, NEW YORK.

DUPLEX cARBUnEf'roR.

Anuncation med may 21, 1924. serial No. 714,853:

. following is a full, clear,`and exact descrip- This invention relates to carburetors and has for an object to provide an improved construction wherein two different kinds of fuel may be used without intermixing.

- Another object of the invention is to provide a carburetor wherein means are provided for feeding two diiferent kinds of fuel, the same being associated with meansv for quickly shifting at any time cert-ain parts` so that either fuel may be supplied from the carburetor.

A further-object, more specifically,` is to provide a double lead-in for fuel in the carburetor with a valve structure for automatically shutting oif one lead-in when the other is turned on so that only one kind of fuel can be utilized at any given time.

In the accompanying drawings- Figure 1 is a longitudinal vertical sectional view through a double carburetor, disclosing an embodiment of the invention, the same being taken approximately on line 1-1 of Figure 2. i

Figure 2 is a. transverse sectional view on the line 2--2 of Figure 1.

Figure 3 is a fragmentary sectional view through Figure 2, approximately on line Figure 4-is an edge view of the structure shown in Figure 1, certain parts being broken away for better illustrating the structure.

Referring to the accompanying drawings by numerals, 1 and 2 indicate float. chambers provided with suitable floats 3 and 4 which are loosely arranged in these chambers and loosely slidlable on the hollow posts 5 and 6. These posts are each provided with one -or more apertures 7 at the bottom and avalve seat 8 below the apertures 7. The threaded outer ends 9 and 10 of the posts' 5 and 6 are connected to suitable supplies of fuel, as for instance, gasoline and kerosene. bsall valve 11 is arranged'to co-act with each of the seats'S, each valve having a rod 12.

'extending loosely through the respective posts and 6 and rigidly secured at their A the carburetor past the upper ends to the disks`13 and ity ofpointed members l'adapted to engage the respective disks 13 ,and 14 for nais-1 ing the disks and the respectiverods 12 as well as the valves 11 for closing the passageways through t-heposts 5 'and.6. By this construction and arrangement, a-'cert-ain level of fuel is maintained independently in 'each of the float chambers 1- and- 2.y Arranged adjacent each of the fioat chambers is what. mav be termed a feeding chamber 16, the re'- spective feeding .chambers being in communication with the chambers 1- and 2 through the apertures-17 and 18. The Elower ends of the respective chambers 16 are closed by suitable plugs 19 while in these chambers there is provided a hollow feeding member or nozzle 20. A needle valve 21co-acts with the upper ends of the nozzles 2O for regulatin'g the How of fuel therethrough; The upper parts of the chambers 16 are in free communication withthe respective passage-ways 22 and 23. These passage-ways 'open' into a bore 24 in the casing 25 of the carburetor. This casing is provided with -a central passage-way 26 having at itslower end a butterfly v alve 27 and also at the upper end a butterfly valve 28. A vent-uri 29 is also preferably provided and positioned so that the mixture flow control valve 3()` will extend through the smallest part thereof.V The mix ture flow control valve 30 is tapered near one end as shown in Figure 2 so as to fit properly in the tapered end of the aperture 24. A spring 32 acting on a suitable stop 33 maintains thee pipe 30 in proper position. This pipe is provided with an operating handle 34 which may extend to any desired point so as to be operated at any time.` The mixture How control valve 30 is provided with a longitudinal bore 35 merging at one end into passage-ways 36 and 37 and at the-opposite end into passage-waysBS and 39.

When the parts are in the position shown in the 'drawings,fuel will be supplied from the float chamber 1 to the aperture or discharge opening 38. It will, of course, be evident that airwill pass around the valve 30 and mix with the fuel above the valve 30 so that a proper mixture may pass out of valve 28. In order to provide some additional auxiliary air, an auxiliary air supply valve 40 isA provided which is held 'seated'by a spring 41 and said spring in turn 1s vmaintained under tension 14. i nach of 4the floats 3 and 4'is provided-:With a plural-l by acup-shaped nut' 42 whereby the tension spring may be varied' and. consequently, the

. y suction required to open valve 4() determined. It will be noted that the va ve 40 normally closes an aperture in the cha ber 4:3 which is in free communication With the interior of thev casing 25 indicated in lFigures 3 and 4.

. In case the float-chamber 1 contains gasoline, a proper supply thereof will be fed to the nozzle 2O and hence to the engine to which other fuel may be turned .on toy the other chamber and by reason of the'heat, as well as the-.structure heretofore described, properly vaporized and more or less gasiied so as to produce desirable results. Vhat I claim is v I A1. A duplex carburetor, comprising a casing provided With a mixture flow control valve having a pair ,of discharge openings #midway its length, a pair of inlet openings near one end functioning at diierent times the carburetor isV connected. Afterfthe en'-n vgine has become heated and it should be .de-

sired to use kerosene or other fuel' in chamber 2, valve could be shifted a quarter of a turn so that the aperture 37 wouldv comeJ into re istry with the'aperture 23. This would su't off the passageway 22 and per- Vmit the suction from the engine to draw in kerosene from the ioat chamber 2. It will benoted that the 'sprayed fuel passing out through the aperture 38 isyquickly mixed with airpassing in through the venturi and thereby produce a good explosive mixture by reason of the even distribution of the, fuel throughout the air supply. In addition, a preliminary mixing of air is provided in the feed chambers 16 by reason ofthe 'factthat each of these chambers is provided wi h a small air inlet X44 so that the fuel supplied to the outlet 38 is in fact, an extremelyl rich mixture of fuel and air which is again diluted with air passing through the venturi 29. In case the suction is suliici'ent-ly great, -a further diluting of the mixture lis produced by the passageof air, throughthe chamber 43. Y

l In order to cause a proper action, both with the gasoline and kerosene or other. fuel, z a water jacket 44 -is provided which is shown as cast integralwith the otherparts of the carburetor, though if-jpreferre'd, it'

might be made separate and connected in any. suitable manner. l This' 'water jacket surrounds the main air inlet and the venturi 29.

'A circulation iof hot water is provided for vthis water jacket. by vhaving the vrespective pipes 45 'and 46 connected lto suitable parts' ofthe water jacket of the engine..I When the engine 1s first started, the gasoline side ofthe carburetor is used until the engine has become heated 'and the` water also heated.

After this has occurred, thejkerosene `or anda central bore connecting said discharge openings with said inlet openings, a pair of float chambers adapted to receive dllferent fuels, means providing a passage-way from therespective float chambers tosaid inlet openings, said inlet openings being` arranged at an angle to Veach other whereby the mixvtrolvalve having a pair of apertures positioned centrally of the air passage-way and extending at right angles to each other, said vmixture flow controljvalve having a longitu- 8'5 dinal passage-way merging near one end into right angle inlet openings, a pair of fue] supply chambers having discharge openings extending to said mixture flow control valve so as tobe brought into registry Wthone of said inlet openings thereof ac' cording to theposition of the mixture liowcontrol valve, a fuel feeding nozzle arranged lin each ofthe fuel supply, chambers, anda {ioat chamber for malntaining a 'supply of fuel in each of the fuel supply chambers.

3. In -a carburetor ofthe charactery de scribed, a mixture flow control valve for cony. trolling the fuel discharged from the carburetor, said mixture rflow control valve comprising a rod having a longitudinal bore for anglesto each other whereby a quarterof a turn of the pipe will .bring either aperture of'both pairs u permost.

y CAlEL GOVERT KREBS.

" part `of its length, said bore at each end 'merging into aperturesl arranged; at right 

